Submit updates

A feed update publishes a new issuer-signed scalar value for a registered feed. Submit the value, and the platform resolves the issuer identity for the feed topic. Check the latest round before your consumers depend on it.

How signed updates work

DALP signs and submits a feed update for the identity authorised for the feed topic. The feed contract validates the issuer identity, signer key purpose, and nonce. It then checks the timestamp and deadline against feed value rules before storing a new round.

Authority resolution depends on the feed topic. The following table shows who can submit and which signing identity the platform uses.

issuerIdentity is the OnchainID contract address for the issuer, not the EOA wallet address. The field appears in nonce requests and submit responses.

Prerequisites

Before submitting feed updates:

1. Confirm the feed is registered and indexed.
2. Confirm the caller is authorised for the feed topic.
3. Know the feed's decimal precision so you can encode the value at the correct magnitude.
4. Read the current nonce for the issuer identity that DALP will use for the topic.

Get the current nonce

Read the nonce for the signing identity on the target feed. For price-topic feeds, use the organisation OnchainID address. For other topics, use the trusted issuer user's OnchainID address.

curl "$DALP_API_URL/system/feeds/0xFeed/nonce/0xIdentityContract" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "issuerIdentity": "0x...",
  "currentNonce": "5",
  "nextNonce": "6"
}

Use nextNonce to find the next strict sequential value the feed contract expects for that issuer. The nonce endpoint reads the feed contract directly and returns the on-chain count plus the next expected number. DALP derives the nonce during submission, so the request body omits the nonce field.

Submit an update

Submit the encoded value and observation timestamp to the feed. When the transaction completes synchronously, the API returns the submitted value, nonce, transaction metadata, and response link:

curl -X POST "$DALP_API_URL/system/feeds/0xFeed/submit" \
  -H "X-Api-Key: $API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "value": "150000000",
    "observedAt": 1700000000,
    "deadline": 0
  }'

Specify the feed address in the URL path. DALP resolves the signing identity from the feed topic and the authenticated context. For price-topic feeds, DALP uses the organisation identity when the caller has the feedsManager system role. For non-price topics, DALP uses the authenticated user's OnchainID identity when it is a trusted issuer for the topic.

If you are updating a token price, prefer the token price endpoint. It applies the token-level setPrice permission, resolves or creates the feed, and sends the update with the organisation issuer identity.

Parameters

Response:

{
  "data": {
    "transactionHash": "0x...",
    "feedAddress": "0x...",
    "value": "150000000",
    "nonce": "6"
  },
  "meta": {
    "txHashes": ["0x..."]
  },
  "links": {
    "self": "/v2/system/feeds/0xFeed/submit"
  }
}

Submit flow

A successful submit stores one new round for the feed. Contract rejection on any field (issuer, signer, nonce, timestamp, deadline, or value) causes the Platform API to return an error. No new round is recorded.

Read feed configuration

Before submitting, query the feed configuration to confirm the decimals precision, the requirePositive constraint, and the driftAllowance. These values are fixed at registration and determine whether the platform accepts your update.

curl "$DALP_API_URL/system/feeds/0xFeed/config" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "subject": "0x...",
  "topicId": "0x...",
  "expectedSchemaHash": "0x...",
  "decimals": 8,
  "description": "USD price feed",
  "historyMode": "BOUNDED",
  "historySize": 100,
  "requirePositive": true,
  "driftAllowance": 300,
  "domainSeparator": "0x...",
  "trustedIssuersRegistry": "0x...",
  "topicSchemeRegistry": "0x..."
}

Key fields:

Check staleness

Consumers that use the feed to value collateral, price settlement, or run reserve checks must verify the value is recent before acting on it. Call the staleness endpoint with your acceptable age threshold, and reject any feed whose isStale field returns true.

curl "$DALP_API_URL/system/feeds/0xFeed/staleness?maxAgeSeconds=3600" \
  -H "X-Api-Key: $API_KEY"

Response:

{
  "feedAddress": "0x...",
  "latestUpdatedAt": "2023-11-14T22:13:20.000Z",
  "currentTimestamp": "2023-11-14T23:11:40.000Z",
  "ageSeconds": 3500,
  "maxAgeSeconds": 3600,
  "isStale": false,
  "roundId": "6",
  "answer": "150000000"
}

The staleness endpoint reads the latest round from the feed contract. It compares the round's update timestamp with the current chain head timestamp. A fresh result does not approve the value by itself. Your workflow still decides whether to accept the feed value for the operation.

CLI equivalents

The DALP CLI exposes the same three operations. Use the CLI for local testing or scripted automation when you prefer not to construct HTTP requests directly.

dalp system feeds nonce --address 0xFeed --issuer-identity 0xIdentityContract
dalp system feeds submit --address 0xFeed --value 150000000 --observed-at 1700000000
dalp system feeds staleness --address 0xFeed --max-age-seconds 3600

Related

• Data feeds overview
• Read data feeds
• Feeds update flow